Well now I know what a 799 head is.
its the sister head to the 243 head..... LOL
the 243 head and 799 head are the best flowing stock LS heads that really come alive with a bit of mild porting. other than the C5 corvette motor with the 243's that got hollow stem valves, all other 243 and 799 heads have the same chambers and ports and stock steel valves.
the 243 is semi-permenant mold (A380 material), the 799 head is sand cast (A356 material), making the 799 head slightly stronger Higher initial yield strength. and a slightly higher hardness
because the head is slightly stronger, means I can port the head a little more, specifically getting closer to the tapped hole for the rocker boss
my main concern is the rocker stud boss break thru. all the people that CNC port the heads break thru on the intake side, and just leave it, then rely on a thread sealer to keep the motor from pulling in oil from the bolt threads. my concern is this leaves an airflow eddy. so I will need to install the bolts and some high-temp aluminum impregnated epoxy like lab metal, devcon or belzona, then dress off.
this is what I started with. crusty and oil coked. both heads had about an 1/8" layer of oil and carbon in the intake track. my guess the motor suffered blow-by from poor rings or the valve seals had gone. either way, the motor these heads came from was sucking in oil on the PCV system
